Apparatus for leveling and smoothing land has heretofore been used for a variety of agricultural and industrial applications for maintenance and tillage operations. In humid areas this equipment has been used to correct surface drainage and for seed bed filling, and on rolling fields to fill and erase small washes and gullies, smooth terraces and benches, and shape up waterways. For industrial applications land levelers are used to work and smooth the land for landscaping and by contractors.
In U.S. Pat. Nos. 2,994,977 and 3,090,141, assigned to the assignee of the present invention, there is disclosed land leveling apparatus having automatic leveling features that maintain the cutting blade on the field grade plane independently of the vertical travel of the rear tractor wheels. The present invention provides advances in implements of the land leveling type and more particularly in apparatus capable of smoothing a wider area with each pass over a field while maintaining the cutting edge in a horizontal plane. In providing a land leveling apparatus of increased width the land leveler apparatus of the present invention is capable of handling greater weights, supporting a wider span, providing required widths during travel on the highway, and avoiding any tendency of the outer extremities of the scraper blade to dip and gauge the ground on turns.
Accordingly, it is an object of the present invention to provide novel and improved apparatus generally of the earth moving type.
Another object of the present invention is to provide a novel land leveling apparatus having a substantially greater leveling capacity.
Still another object of the present invention is to provide a novel land leveling attachment having articulated side blade sections that fold up for transport purposes, have upper and lower level adjustments and are positively locked in the lowered working position.
A further object of the present invention is to provide a novel and improved hitch for a land leveling attachment that affords efficient coupling and decoupling with a conventional hydraulically powered tractor linkage and allows both vertical and twisting motion of the tractor independently of the leveling attachment.
Yet another object of the present invention is to provide a novel and improved automatic leveling assembly for a land leveling apparatus that adjusts as the tractor moves up and down to maintain the scraping edge of the scraping blade in the ground plane of the rear leveler frame wheels and front tractor wheels independently of the vertical movement of the rear tractor wheels.
Still a further object of the present invention is to provide a novel and improved land leveling attachment that is readily adapted to different categories of tractor linkages.